Today’s problem — free all day, every step. Every day has one.
Two workers — finishing a job together
Worker A can complete a job in 5 days. Worker B can complete the same job in 10 days. They work together for 2 days, then Worker A stops. How many more days does Worker B need to finish?
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65 worked examples are free without a code, two from every pattern. No account, either way.
The pattern behind it: Number × value
One batch repeats. Work out one batch, then multiply.
In this one. Give the job a unit count both times divide into (10), so each worker's speed becomes a whole number of units per day — and rates in the same units add.
Also uses: Same time, same distance
How to spot it
Items are described as a fixed group or ratio that repeats, such as tiles following a pattern, snacks sold in a fixed mix, or a rate given per hour or per item.
Common mistake
Children start from the grand total instead of first working out what one batch is worth. In rate questions they also confuse a duration with a clock time.
Try one like it
Standard Buns and muffins — 3 : 5 worth $55 A bakery sells buns and muffins in the ratio of 3 buns to 5 muffins. Each bun costs $2, and each muffin costs $1. If the total val…The 33 problem patterns
All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.
A PDF, and a note when new solutions go up.